It is often desirable to adjust the distance from a floor to a suspended object. As an example, the suspended objects may include ventilation ducting, ceiling panels, electrical conduits, or sprinkler heads. Typically, these objects are suspended from the ceiling or other support members using threaded rods with nuts that are axially positioned along the rod to locate the suspended object.
One standard version of an adjustable length telescopic connector used in the fire sprinkler industry comprises an outer member having a threaded opening at one end for screwing onto a drop pipe, the drop pipe attaching to a support member such as a ceiling or a rafter, and at the other end having interior threads. An inner member having threads on its outer surface is then screwed into the outer member. By varying the amount of the inner member which is screwed into the outer member, the length of the connector may be varied. The lower end of the inner member is often threaded, interiorly or exteriorly, to accommodate connection with an object to be suspended such as a sprinkler head or the like.
Although this standard type of connection works satisfactorily, the close tolerances required for the threaded connection between the inner and outer members generally requires the connector to be assembled off site or the use on site of a skilled worker who must be taken from other jobs for a significant period of time. Further, if the threads become damaged or corroded, later repositioning requires reworking the threads.